The unique role of the trigeminal autonomic reflex and its modulation in primary headache disorders

TY - JOUR

T1 - The unique role of the trigeminal autonomic reflex and its modulation in primary headache disorders

AU - Möller, Maike

AU - May, Arne

PY - 2019/6

Y1 - 2019/6

N2 - PURPOSE OF REVIEW: The trigeminal autonomic reflex is a physiological reflex with an important protective function which also plays a role in pathophysiological conditions, such as primary headache. It is not understood whether the autonomic symptoms in trigeminal autonomic cephalalgias and migraine are the consequence of severe trigeminal discharge or indeed directly driven by central generators as part of the pathophysiology, underlying these syndromes.RECENT FINDINGS: Modulating this reflex, and particularly the parasympathetic reflex arc, has been shown to be effective in treating headache. Among these modulators, left noninvasive vagal nerve stimulation has been shown to bilaterally inhibit the parasympathetic output of the reflex. Furthermore, the peripheral activation of the reflex, resulting in parasympathetic discharge, is not sufficient to provoke headache attacks in cluster headache patients, suggesting a central modulation.SUMMARY: Here, we review the anatomy and physiology of the trigeminal autonomic reflex and its involvement in primary headache. Possible candidates who have a modulating effect, including neurostimulation and pharmacological approaches, are described.

AB - PURPOSE OF REVIEW: The trigeminal autonomic reflex is a physiological reflex with an important protective function which also plays a role in pathophysiological conditions, such as primary headache. It is not understood whether the autonomic symptoms in trigeminal autonomic cephalalgias and migraine are the consequence of severe trigeminal discharge or indeed directly driven by central generators as part of the pathophysiology, underlying these syndromes.RECENT FINDINGS: Modulating this reflex, and particularly the parasympathetic reflex arc, has been shown to be effective in treating headache. Among these modulators, left noninvasive vagal nerve stimulation has been shown to bilaterally inhibit the parasympathetic output of the reflex. Furthermore, the peripheral activation of the reflex, resulting in parasympathetic discharge, is not sufficient to provoke headache attacks in cluster headache patients, suggesting a central modulation.SUMMARY: Here, we review the anatomy and physiology of the trigeminal autonomic reflex and its involvement in primary headache. Possible candidates who have a modulating effect, including neurostimulation and pharmacological approaches, are described.

KW - Autonomic Nervous System/physiopathology

KW - Humans

KW - Reflex

KW - Trigeminal Autonomic Cephalalgias/physiopathology

U2 - 10.1097/WCO.0000000000000691

DO - 10.1097/WCO.0000000000000691

M3 - SCORING: Review article

C2 - 30865010

VL - 32

SP - 438

EP - 442

JO - CURR OPIN NEUROL

JF - CURR OPIN NEUROL

SN - 1350-7540

IS - 3

ER -